Engine oil quality, the tread on the tyres and cooling system performance are common elements we regularly look over and service on our vehicles. But when was the last time you thought about your automatic transmission fluid? Maybe you don’t know much about this important component?

We’ve put together a beginner’s guide to automatic transmission fluid that answers five of your most common questions that will help you get the best performance and life out of your transmission.

1. What is the transmission fluid?

Automatic transmission fluid (also known as ATF) lubricates, cleans and protects the moving parts of your transmission. Importantly, the fluid also acts as a coolant for the transmission by transferring excess heat away to the vehicle’s transmission cooler.

2. Why does transmission fluid need to be changed regularly?

Just like your engine oil, transmission fluid breaks down over time, particularly if it has been exposed to hot conditions, and when this happens, your transmission might not perform as it should. If your fluid is degraded or the level is incorrect, the shifting performance, fuel economy and smoothness will worsen. Eventually, you could experience trouble changing gears. Worse, your gears may not change at all leaving you with a costly repair bill.

3. How often should you change your transmission fluid?

You should refer to the manufacturer’s recommendations for transmission fluid change intervals as this differs depending on the type of transmission your vehicle has. For example:

As a general rule, your transmission fluid level and quality should be checked, and changed if required, each time the engine oil is changed.

Bear in mind that transmission fluid doesn’t get ‘used up’ like engine oil, so if your levels are low, it’s likely your transmission has a leak.

4. How do you check your transmission fluid?

Transmission fluid can be easily checked by using the dipstick. Not sure where this is located? Refer to your owner’s manual. Some transmissions are not fitted with a dipstick which can make checking the levels yourself difficult.

If your transmission has a dipstick, follow these five simple steps:

Locate your transmission dipstick.

Warm up your vehicle.

Pull out the dipstick and wipe away the excess fluid with a rag.

Reinsert and pull it out again.

Check the fluid for colour and level.

The transmission fluid should be either a bright red or translucent yellow, depending on the vehicle. If it’s dark and a burnt brown colour it needs replacing. Fluid which has degraded can sometimes have a burnt smell.

5. Can you change transmission fluid yourself?

Yes, although transmission servicing can be messy and difficult on some BMW models which do not have a drain plug.

The most important thing to remember before you attempt any DIY vehicle servicing is to ensure you know what you are doing. Is the research you’ve done or the advice you’ve received for your specific vehicle make and model? If not, contact your local dealer or mechanic and book a service.

Other things to remember:

Use the correct fluid specified for your transmission. The team at Run Auto Parts can help you select compatible products for your vehicle if you are unsure.

It’s vital that the transmission fluid is filled to the correct level. This is an important procedure, so again if you are not confident, this might be one job that’s best left to the experts.

Welcome to Run Auto

We’re Australia’s European Car Parts Specialists and we want to make your car as good as it can be. We sell quality OEM and Aftermarket parts for all European cars including; Audi, VW, Skoda, BMW, Mercedes, Porsche, Renault, Citroen & Peugeot. Find out more....